A researcher is carrying out an experiment where she labels a protein with a fluorescent tag (so she can visualize its location
in a cell) and introduces this tagged protein into the lumen of a single thylakoid. She observes her treated cells periodically and notices that the labeled protein can move between grana and is always in the lumen, but is never observed in the stroma. What can she deduce?
The protein likely travels through a common lumen shared by thylakoid membranes and grana, and cannot easily diffuse through the thylakoid membrane.
Explanation:
There is a lot of scientific research in which a specific molecule can be labeled with some fluorescent marker (usually carbon 14). This type of marking allows the researcher to make observations about the movement of these molecules, as you can see in the question above. About the research shown in the question, the researcher realized that the protein labeled with the fluorescent marker moved between the grana and was always in the lumen, so she can conclude that the selocomovement protein moved through the lumen that is shared between the tilacoid membranes and the grana.
(D) Both perform photosynthesis is the observation that led researchers to propose that chloroplasts evolved from cyanobacteria. Chloroplasts is the area where photosynthesis takes place. It is a green organelle in a plant cell. Pigments called the chloros in a chlorophyll are needed for the photosynthesis. Cyanobacteria or blue-gree algae contains a blue photosynthetic pigment and a chlorophyll for photosynthesis.
